The invention relates to a safety device for vehicles and, more particularly, to a safety device for motor vehicles whose passenger compartment has at least one opening, such as a roof opening or side window, which can be optionally locked or released by a closing element coupled to a displacement drive. The safety device has a sensor system which detects a situation which adversely affects the safety of the vehicle occupants and triggers the closing movement of the closing element from its open or partially open position. A locking device holds the closing element in its closed position.
In a known safety device of the above-mentioned type, such as in German Patent Document DE 35 12 177 C2, the sensor system responds when the driving speed of the vehicle exceeds a predetermined threshold value and causes the displacement drive to drive the closing element in the closing direction until the opening is completely closed. As a result, the driving safety is prevented from being adversely affected by the increased driving resistance and driving noise occurring at higher driving speeds. However, when driving below the predetermined speed limit, this type of safety device does not prevent the occupants from being thrown out through a non-closed opening. Further, it does not prevent injuries from the entry of the foreign bodies such as branches and stones or by contact with parts outside the vehicle, e.g. the roadway, in the event of a car accident, for example if the vehicle rolls over.
In vehicles with a folding roof, it is known from German Patent Document DE-PS 263 058 to lock the roof folded in the open position with pretensioning and to connect it to a bumper in a detachable manner. The detachable manner operates in such a way that, in the event of an impact of the bumper against an obstacle, the locking is triggered, after which the folding roof is automatically extended. This device assumes the presence of a closing element which is deformable and tensionable per se and, despite a costly and also fault-prone unlocking mechanism, is not effective in all accident situations.
In motor vehicles with roll bars it is already known from German Patent Document DE 35 45 874 C1 to detect vehicle deceleration by means of a sensor and in the event of a predetermined value being exceeded to generate a switching signal which activates a drive device which extends the roll bar. A second sensor detects vehicle inclinations with respect to the X-axis of the vehicle and a third sensor detects the road grip of at least one rear wheel of the vehicle. Both sensors generate corresponding switching signals if the preset values of the vehicle inclinations or of the rebound travel of the rear wheel are exceeded. The switching signals of the, in total, three sensors are logically connected to one another in such a way that the drive device for the roll bar is only activated if at the same time the rear wheel lifts off from the ground and at least one inclination value of the vehicle inclination is exceeded.
From EP 0 309 686 A1 it is also known to generate in a crash situation a control pulse by means of which a support piston of a piston cylinder unit is instantaneously extended and thus a roll bar is moved from a lowered position of rest into a raised supporting position in which it protects the vehicle occupants from injuries if the vehicle rolls over. For the instantaneous extension of the support piston, the roll bar is acted upon by a compression spring acting as an energy store, which is locked in the tensioned state. By means of the control pulse triggered in the crash situation the locking device is deactivated.
In a safety device for motor-vehicle sliding roofs it is known from German Patent Document DE 30 15 836 C2 to prevent the roof cover, which can be driven by means of a displacement drive, from moving into its closed position if there is an obstacle in the region of the roof opening. For this purpose, the safety device has at least one plate-shaped or strip-shaped sensor, which extends at least along a part of the circumference of the roof opening or of the lid cover, and also a detector which cooperates with the latter and responds when the sensor meets an obstacle.
There is therefore needed a safety device, of the above-mentioned type, which in the event of an accident offers a secure protection for the vehicle occupants against injury by foreign bodies, whether by objects from outside the passenger compartment or by the closing of the closing element itself, and in particular against being thrown out of the vehicle passenger compartment.
These needs are met according to the present invention in a safety device for vehicles whose passenger compartment has at least one opening, such as a roof opening or side window, which can be optionally locked or released by a closing element coupled to a displacement drive. The safety device has a sensor system which detects a situation which adversely affects the safety of the vehicle occupants and triggers the closing movement of the closing element from its open or partially open position. A locking device holds the closing element in its closed position. A quick-acting closing device, which is independent of the displacement drive, is provided for the closing element. The sensor system detects the vehicle deceleration in the driving direction and activates the closing device when a preset value of the vehicle deceleration is exceeded and activates the locking device as soon as the closing element reaches its closed position. The sensor system has components for detecting if vehicle occupants are caught in the closing movement of the closing element and, when these components respond, activates in advance the locking device as a stop for limiting the closing movement of the closing element.
The safety device according to the present invention has the advantage that with a suitable selection of the preset value of the vehicle deceleration, the opening is already closed before the vehicle strikes an obstacle. By means of the locking device which is effective in the closed position of the closing element, the closing element is also prevented from being torn out of its guides by inertial forces in which event would place the vehicle occupant's protection again at risk. At the said time, it is ensured that no vehicle occupant can be injured by the closing element which closes the opening if, for whatever reason, parts of the body of a vehicle occupant should already be placed in the opening during the closing movement of the closing element. By simultaneously using the closing device as a stop for limiting the closing movement of the locking element in the event of a vehicle occupant being caught in it, constructional space, construction weight and manufacturing costs of the safety device are reduced.
In an advantageous embodiment of the invention the closing device is provided with an "energy store" which, upon being activated, brings about a rapid closing movement of the closing element. The term "energy store" is to be understood in the broadest sense and should cover both mechanical stores, such as spring energy stores, and pneumatic and hydraulic stores, as well as stores in which the energy is present in the form of chemical bonds, such as for example in drive units of belt tautening devices which are activated pyrotechnically.
If, according to the present invention, the sensor system also detects inclined positions of the vehicle which do not occur during fault-free driving, the closing of the opening can be triggered already at the beginning of a rolling over of the vehicle. The inclined position of the vehicle can be detected, for example, in a known manner by sensors which monitor the road contact of the vehicle wheels. The costs of the safety device can be reduced if sensors are used which are provided for the introduction of other safety measures, e.g. for belt tautening or for controlling a roll bar.
It is a further advantage of the present invention to ensure that the closing device operates satisfactorily even if the displacement of the closing element is subject to increased friction or is provided with a step-down gear.
If the energy store of the closing device is constructed as a spring energy store which can be moved into the loading position by the displacement drive of the closing element during its opening movement, with the arrangement of a coupling in the displacement drive, the advantage is also obtained that the triggering device for the energy store and the decoupling device can be formed by one and the same component.
Other objects, advantages and novel features of the present invention will become apparent from the following detailed description of the invention when considered in conjunction with the accompanying drawings.